Table 1.

Adapted classification criteria based on injury pathophysiology and tissue changes [11,12,13].

Classification	Description	Clinical Signs	Cytokine	Duration Time	Outcomes Cellular/Tissue
Acute Inflammation	−Small vessels dilation. −Increased microvascular permeability. −Leukocytes migration: the neutrophils that predominate in the first 6 to 24 h are gradually replaced by macrophages from 24 to 48 h after injury.	−Pain −Fever −Edema −Blush	TNF IL-1 IL-6 IL-17 Prostaglandins Bradykinin Reactive oxygen species (ROS)	24–48 h	−Complete recovery −Reversible cell function −Death cell −Progressive chronic inflammation
Transition Period	Between 48 h and 7 days, features of acute and chronic inflammation can be found. This period can be called the transition period, in which the diagnosis of the injury as acute or chronic is not clear.
Chronic Inflammation	−Long-lasting response starting 48 h after injury and lasting for weeks or months. In this phase, inflammation, tissue damage, and recovery attempts coexist in different combinations. −In most chronic inflammatory reactions, the dominant cells are macrophages and T lymphocytes.	−Pain −Atrophy	IL-12 INF- IL-17	≥7 days	−Fibrosis −Loss of function −Perhaps even tissue breakdown may occur. −Granulation tissue −Neuropathic pain −Neural fibrosis −Anxiety −Depression